#region PDFsharp - A .NET library for processing PDF
//
// Authors:
//   Stefan Lange
//
// Copyright (c) 2005-2017 empira Software GmbH, Cologne Area (Germany)
//
// http://www.pdfsharp.com
// http://sourceforge.net/projects/pdfsharp
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software"),
// to deal in the Software without restriction, including without limitation
// the rights to use, copy, modify, merge, publish, distribute, sublicense,
// and/or sell copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
// THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 
// DEALINGS IN THE SOFTWARE.
#endregion

using System;
using System.Diagnostics;
using System.Text;

namespace PdfSharp.Pdf.Internal
{
    /// <summary>
    /// An encoder for PDF DocEncoding.
    /// </summary>
    internal sealed class DocEncoding : Encoding
    {
        public DocEncoding()
        { }

        public override int GetByteCount(char[] chars, int index, int count)
        {
            return PdfEncoders.WinAnsiEncoding.GetByteCount(chars, index, count);
        }

        public override int GetBytes(char[] chars, int charIndex, int charCount, byte[] bytes, int byteIndex)
        {
            byte[] ansi = PdfEncoders.WinAnsiEncoding.GetBytes(chars, charIndex, charCount);
            for (int idx = 0, count = ansi.Length; count > 0; idx++, byteIndex++, count--)
                bytes[byteIndex] = AnsiToDoc[ansi[idx]];
            return ansi.Length;
        }

        public override int GetCharCount(byte[] bytes, int index, int count)
        {
            //return PdfEncoders.WinAnsiEncoding.GetCharCount(bytes, index, count);
            Debug.Assert(PdfEncoders.WinAnsiEncoding.GetCharCount(bytes, index, count) == count);
            return count;
        }

        public override int GetChars(byte[] bytes, int byteIndex, int byteCount, char[] chars, int charIndex)
        {
            PdfDocToUnicode.GetType();
            throw new NotImplementedException("GetChars");
            //for (; byteCount > 0; byteIndex++, charIndex++, byteCount--)
            //  chars[charIndex] = (char)bytes[byteIndex];
            //return byteCount;
        }

        public override int GetMaxByteCount(int charCount)
        {
            return charCount;
        }

        public override int GetMaxCharCount(int byteCount)
        {
            return byteCount;
        }

        /// <summary>
        /// Converts WinAnsi to DocEncode characters. Based upon PDF Reference 1.6.
        /// </summary>
        static readonly byte[] AnsiToDoc = new byte[256]
        {
            //         x0    x1    x2    x3    x4    x5    x6    x7    x8    x9    xa    xb    xc    xd    xe    xf
            /* 00 */ 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F,
            /* 10 */ 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F,
            /* 20 */ 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x2F,
            /* 30 */ 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, 0x3B, 0x3C, 0x3D, 0x3E, 0x3F,
            /* 40 */ 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4A, 0x4B, 0x4C, 0x4D, 0x4E, 0x4F,
            /* 50 */ 0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5A, 0x5B, 0x5C, 0x5D, 0x5E, 0x5F,
            /* 60 */ 0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6A, 0x6B, 0x6C, 0x6D, 0x6E, 0x6F,
            /* 70 */ 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7A, 0x7B, 0x7C, 0x7D, 0x7E, 0x7F,
            /* 80 */ 0xA0, 0x81, 0x91, 0x83, 0x8C, 0x83, 0x81, 0x82, 0x1A, 0x89, 0x97, 0x88, 0x96, 0x8D, 0x99, 0x8F,
            /* 90 */ 0x90, 0x8F, 0x90, 0x8D, 0x8E, 0x80, 0x85, 0x84, 0x1F, 0x92, 0x90, 0x89, 0x9C, 0x9D, 0x9E, 0x98,
            /* a0 */ 0x20, 0xA1, 0xA2, 0xA3, 0xA4, 0xA5, 0xA6, 0xA7, 0xA8, 0xA9, 0xAA, 0xAB, 0xAC, 0xAD, 0xAE, 0xAF,
            /* b0 */ 0xB0, 0xB1, 0xB2, 0xB3, 0xB4, 0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xBA, 0xBB, 0xBC, 0xBD, 0xBE, 0xBF,
            /* c0 */ 0xC0, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, 0xCA, 0xCB, 0xCC, 0xCD, 0xCE, 0xCF,
            /* d0 */ 0xD0, 0xD1, 0xD2, 0xD3, 0xD4, 0xD5, 0xD6, 0xD7, 0xD8, 0xD9, 0xDA, 0xDB, 0xDC, 0xDD, 0xDE, 0xDF,
            /* e0 */ 0xE0, 0xE1, 0xE2, 0xE3, 0xE4, 0xE5, 0xE6, 0xE7, 0xE8, 0xE9, 0xEA, 0xEB, 0xEC, 0xED, 0xEE, 0xEF,
            /* f0 */ 0xF0, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7, 0xF8, 0xF9, 0xFA, 0xFB, 0xFC, 0xFD, 0xFE, 0xFF,

            ////// Converts WinAnsi to DocEncode characters. Incomplete, just maps € and some other characters.
            //////         x0    x1    x2    x3    x4    x5    x6    x7    x8    x9    xa    xb    xc    xd    xe    xf
            /////* 00 */ 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F,
            /////* 10 */ 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F,
            /////* 20 */ 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x2F,
            /////* 30 */ 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, 0x3B, 0x3C, 0x3D, 0x3E, 0x3F,
            /////* 40 */ 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4A, 0x4B, 0x4C, 0x4D, 0x4E, 0x4F,
            /////* 50 */ 0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5A, 0x5B, 0x5C, 0x5D, 0x5E, 0x5F,
            /////* 60 */ 0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6A, 0x6B, 0x6C, 0x6D, 0x6E, 0x6F,
            /////* 70 */ 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7A, 0x7B, 0x7C, 0x7D, 0x7E, 0x7F,
            /////* 80 */ 0xA0,#0x7F, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8A, 0x8B, 0x8C, 0x8D, 0x8E, 0x8F,
            /////* 90 */ 0x90, 0x91, 0x92, 0x93, 0x94, 0x95,#0x8A,#0x8C, 0x98, 0x99, 0x9A, 0x9B, 0x9C, 0x9D, 0x9E, 0x9F,
            /////* a0 */ 0x20, 0xA1, 0xA2, 0xA3, 0xA4, 0xA5, 0xA6, 0xA7, 0xA8, 0xA9, 0xAA, 0xAB, 0xAC, 0xAD, 0xAE, 0xAF,
            /////* b0 */ 0xB0, 0xB1, 0xB2, 0xB3, 0xB4, 0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xBA, 0xBB, 0xBC, 0xBD, 0xBE, 0xBF,
            /////* c0 */ 0xC0, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, 0xCA, 0xCB, 0xCC, 0xCD, 0xCE, 0xCF,
            /////* d0 */ 0xD0, 0xD1, 0xD2, 0xD3, 0xD4, 0xD5, 0xD6, 0xD7, 0xD8, 0xD9, 0xDA, 0xDB, 0xDC, 0xDD, 0xDE, 0xDF,
            /////* e0 */ 0xE0, 0xE1, 0xE2, 0xE3, 0xE4, 0xE5, 0xE6, 0xE7, 0xE8, 0xE9, 0xEA, 0xEB, 0xEC, 0xED, 0xEE, 0xEF,
            /////* f0 */ 0xF0, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7, 0xF8, 0xF9, 0xFA, 0xFB, 0xFC, 0xFD, 0xFE, 0xFF,
        };

        // TODO: use this table
        static readonly char[] PdfDocToUnicode = new char[]
        {
            '\x00', '\x01', '\x02', '\x03', '\x04', '\x05', '\x06', '\x07', '\x08', '\x09', '\x0A', '\x0B', '\x0C', '\x0D', '\x0E', '\x0F',
            '\x10', '\x11', '\x12', '\x13', '\x14', '\x15', '\x16', '\x17', '\x18', '\x19', '\x1A', '\x1B', '\x1C', '\x1D', '\x1E', '\x1F',
            '\x20', '\x21', '\x22', '\x23', '\x24', '\x25', '\x26', '\x27', '\x28', '\x29', '\x2A', '\x2B', '\x2C', '\x2D', '\x2E', '\x2F',
            '\x30', '\x31', '\x32', '\x33', '\x34', '\x35', '\x36', '\x37', '\x38', '\x39', '\x3A', '\x3B', '\x3C', '\x3D', '\x3E', '\x3F',
            '\x40', '\x41', '\x42', '\x43', '\x44', '\x45', '\x46', '\x47', '\x48', '\x49', '\x4A', '\x4B', '\x4C', '\x4D', '\x4E', '\x4F',
            '\x50', '\x51', '\x52', '\x53', '\x54', '\x55', '\x56', '\x57', '\x58', '\x59', '\x5A', '\x5B', '\x5C', '\x5D', '\x5E', '\x5F',
            '\x60', '\x61', '\x62', '\x63', '\x64', '\x65', '\x66', '\x67', '\x68', '\x69', '\x6A', '\x6B', '\x6C', '\x6D', '\x6E', '\x6F',
            '\x70', '\x71', '\x72', '\x73', '\x74', '\x75', '\x76', '\x77', '\x78', '\x79', '\x7A', '\x7B', '\x7C', '\x7D', '\x7E', '\x7F',
            '\x2022', '\x2020', '\x2021', '\x2026', '\x2014', '\x2013', '\x0192', '\x2044', '\x2039', '\x203A', '\x2212', '\x2030', '\x201E', '\x201C', '\x201D', '\x2018',
            '\x2019', '\x201A', '\x2122', '\xFB01', '\xFB02', '\x0141', '\x0152', '\x0160', '\x0178', '\x017D', '\x0131', '\x0142', '\x0153', '\x0161', '\x017E', '\xFFFD',
            '\x20AC', '\xA1', '\xA2', '\xA3', '\xA4', '\xA5', '\xA6', '\xA7', '\xA8', '\xA9', '\xAA', '\xAB', '\xAC', '\xAD', '\xAE', '\xAF',
            '\xB0', '\xB1', '\xB2', '\xB3', '\xB4', '\xB5', '\xB6', '\xB7', '\xB8', '\xB9', '\xBA', '\xBB', '\xBC', '\xBD', '\xBE', '\xBF',
            '\xC0', '\xC1', '\xC2', '\xC3', '\xC4', '\xC5', '\xC6', '\xC7', '\xC8', '\xC9', '\xCA', '\xCB', '\xCC', '\xCD', '\xCE', '\xCF',
            '\xD0', '\xD1', '\xD2', '\xD3', '\xD4', '\xD5', '\xD6', '\xD7', '\xD8', '\xD9', '\xDA', '\xDB', '\xDC', '\xDD', '\xDE', '\xDF',
            '\xE0', '\xE1', '\xE2', '\xE3', '\xE4', '\xE5', '\xE6', '\xE7', '\xE8', '\xE9', '\xEA', '\xEB', '\xEC', '\xED', '\xEE', '\xEF',
            '\xF0', '\xF1', '\xF2', '\xF3', '\xF4', '\xF5', '\xF6', '\xF7', '\xF8', '\xF9', '\xFA', '\xFB', '\xFC', '\xFD', '\xFE', '\xFF',
        };
    }
}
